Prevention of nosocomial legionellosis by best water management: comparison of three decontamination methods.

BACKGROUND: Since 2000, the National Health System has adopted international guidelines for assessing Legionella spp. in hospital water systems. The control of water contamination by Legionella spp. is still a matter of research concerning the most effective method in preventing nosocomial infections. AIM: To compare three different decontamination methods by monitoring colony-forming unit count and number of hospital-acquired legionellosis cases. A secondary objective was to evaluate the long-term effects of the preventive measures on the water pipes. METHODS: A protocol was developed for the selection of high-risk sampling sites and for the testing of three disinfection methods over the course of 19 years: hyperchlorination and thermal shock (period A, 2000-2005); copper-silver ionization (period B, 2006-2010); and integration of pre-filtering, filtering, pipe-protecting products, and remote control with chlorine dioxide (ClO2) (period C, 2011-2018). FINDINGS: The use of shock disinfection and hyperchlorination led to a decrease in contamination level immediately after the procedure, but then it rose again to the previous level in two months. Both copper-silver ionization and ClO2 disinfection showed a stable and durable decrease in contamination level. Throughout these three phases, six cases of Legionella spp. occurred during period A, six cases during period B, and three cases during period C. With regard to the damage of water pipes, effective copper-silver levels caused corrosion and calcification in water pipes. CONCLUSION: Both copper-silver ionization and ClO2 properly controlled Legionella spp. contamination. ClO2 significantly reduced the number of positive sites (P < 0.001) without damaging the pipelines.

Anisakis spp. larvae in different kinds of ready to eat products made of anchovies (Engraulis encrasicolus) sold in Italian supermarkets.

In this study the occurrence of visible anisakid larvae in semi-preserved anchovy products sold on the Italian market was investigated. Totally, 107 ready to eat products (33 salted-ripened, 49 in oil and 25 marinated) were sampled. Each sample was digested, then the digested material was observed under natural and UV light. Parasites were counted, collected and microscopically identified to genus level. A representative subset was molecularly identified using the cox2 gene. At least one visible Anisakis sp. larva was found in 54.2% of the total 107 products analysed and totally 1283 dead larvae were collected. Anisakis sp. larvae were found in all the 33 salted products and 1139 (88.8%) larvae were collected, with a range of 1-105 parasites per product. Larval density per gram was 0.13. Anisakis sp. larvae were found in 49.0% of the products in oil and 143 (11.1%) larvae were isolated, with a range of 0-28 and a density of 0.03. Only 1 larva was found in the 25 marinated products (4.0%, density 0.00). A highly significant difference between all the product categories in respect of number of larvae per product, frequency of products contaminated by at least one larva and larval density per gram was found. Within the subset of larvae molecularly analysed (n=122), 92 (75.4%) were identified as A. pegreffii and 30 (24.6%) as A. simplex. This study showed that semi-preserved anchovy products heavily contaminated with Anisakis spp. larvae reach the market. Beyond the negligible risk for anisakidosis, the presence of dead visible parasites may cause immediate rejection in consumers. In addition, the potential risk related to allergic reactions in sensitized individuals needs to be further assessed. In order to avoid commercialization of obviously contaminated products, fresh anchovies' batches intended for the production of such products should be accurately selected by the processing industry applying inspection methods.

[Indoor air quality in an Italian military submarine]. / Qualità dell'aria in una nave sommergibile della marina militare Italiana in condizioni operative.

In recent years there has been increasing interest on studies concerning indoor air quality and focusing on risk factors for exposed subjects. Particularly, airborne chemicals, whose adverse effects are well known, have been identified and determined in means of transport as in other indoor places. As concerns chemical air concentrations in submarines, only a limited number of studies have been published. This paper reports measured concentration data for organic compounds (total volatile organic compounds, substances with a chemical bond S-O, nitrogen compounds, carbon monoxide, carbon dioxide, and different organic solvents) in the air sampled during an 8-h period in an Italian Military submarine, under routine operations. We observed that a periodicalfresh-air intake operation (snorkel) might cause temporary increase of contaminants levels in indoor air. Moreover, we could find that pollutants sometimes reach notable peak concentrations being potentially able to induce adverse health effects in crewmembers. Our data highlight the need to promote further investigations.

[Monitoring air dispersed concentrations of aldehydes during the use of ortho-phthalaldehyde and glutaraldehyde for high disinfection of endoscopes]. / Monitoraggio delle concentrazioni aerodisperse di aldeidi durante l'utilizzo di orto-ftalaldeide e glutaraldeide per l'alta disinfezione degli endoscopi.

Solutions of glutaraldehyde (GTA) and ortho-phthalaldehyde (OPA) can both be used for low-temperature disinfection of endoscopes. Currently, GTA is being replaced by OPA (an aromatic dialdehyde) at the San Matteo Hospital, as OPA is less dangerous for health care workers than GTA, but has a similar capacity to kill viruses, bacteria and spores. The aim of the study was to compare air levels of GTA and OPA in several endoscopy units at our hospital. The air samples were analysed by means of both Infrared Spectroscopy (IR) and HPLC-UV (High Performance Liquid Chromatography with UV detection). The HPLC method gave a much lower aldehyde value when using OPA (8.4 micrograms/m3) compared to that obtained when GTA was used to disinfect endoscopes (21.279.3 micrograms/m3). Both HPLC and IR methods detected low levels of OPA in air, the mean values being below 10 micrograms/m3. In addition, we studied the resistance of various types of gloves to OPA. Tests showed that OPA permeated vinyl gloves more rapidly (26,628 ng/cm2 per hour) than nitrile gloves (13.9 ng/cm2 per hour).

[Proposed microbiological indexes for the assessment of air quality in buildings]. / Proposta di indici microbiologici per la valutazione della qualità dell'aria degli edifici.

An assessment of biological risk in the workplace requires the measurement of microorganisms present in the air. Although it is currently difficult to establish a dose-response relationship on the basis of existing epidemiological data, the number and types of microorganisms present offer a useful index when evaluating the quality of the air. Using the results obtained from a study of 226 different offices located in buildings equipped with forced ventilation we propose an assessment of contamination levels based on a Global Index of Microbial Contamination/m3 (GIMC/m3). This index is calculated as the sum of the values of the total microbial count determined for mesophilic bacteria, psychrophilic bacteria and fungi in all sampled areas. GIMC/m3 fluctuates between a minimum value of 23 and a maximum value of 18.069: the mean value varies depending on the ventilation system mode setting, with a value of 145 when operating in the heating mode, 265 in the air-conditioning mode and 258 under simple forced ventilation. 95.5% of the offices under study had a GIMC/m3 value of below 1000: this value is proposed as a threshold limit above which a more extensive assessment of contamination levels based on the measurement of further microbiological indexes should be carried out. To this aim we propose an Index of Mesophilic bacterial Contamination (IMC), obtained by calculating the ratio between the CFU/m3 value measured for mesophilic and psychrophilic bacteria in the same sampling point. The measurement of the Amplification Index (AI) completes the evaluation and this is determined by calculating the ratio between the GICM/m3 values measured inside the building and those measured outside. When considering these observations as a whole we are able to classify the various work areas under study into groups and categories according to the observed values of the proposed microbial contamination indexes.

[Evaluation and quantification of biologic risk in the hospital setting with ATP determination on work surfaces]. / Valutazione e quantificazione del rischio biologico in ambito ospedaliero mediante determinazione dell'ATP sulle superfici di lavoro.

The purpose of this study was to establish whether a method of determining ATP levels using the HY-Lite system could be reliably applied in the various hospital workplaces. We estimated the correlation between ATP levels and the number of C.F.U. (Colony Forming Units), observed correlation r = 0.96. We established hygienically acceptable values for each environment, and drew up reference tables. The study reveals that conditions of high bacterial and fungine contamination can occur, albeit the agents are not normally pathogenic is so far as they consist of common environmental pollutants. Consequently, these results emphasize the need to apply strict sanitization and hygienic measures, that health workers must be suitably trained to deal with follow. The results of the sampling appear to suggest that condition of potential biological risk for workers are largely due to incorrect work procedure in workplaces where pathologic agents are present.

[Epidemiologic study on the prevalence of low back pain in health personnel exposed to manual handling tasks]. / Studio epidemiologico sulla prevalenza della lombalgia nel personale sanitario esposto a movimentazione manuale dei carichi.

An epidemiological study on the prevalence rate of low back pain among health care workers exposed to manual handling tasks and physical work load was performed. A representative sample (n. 1053) of nursing staff working at the San Matteo Hospital in Pavia was studied using a questionnaire with the purpose of evaluating the prevalence rate of low back pain and related risk factors. 86.4% of the subjects admitted having suffered from back pain at some stage in their life and 71.0% complained of back pain in the 3 months prior to answering the questionnaire. Multivariate logistic regression analysis revealed a significant correlation between low back pain, female gender and specific nursing activities. A significant correlation was found between smoking (> 20 cigarettes per day) and the presence of low back pain, due to intervertebral disk pathology. A statistically significant difference (p < 0.0001) was found in the average degree of disability between healthy nurses (1.3), those with low back pain taking analgesic drugs (5.9) and nurses suffering from low back pain without taking drugs (3.8).

[Evaluation of a protocol of health surveillance for the personnel exposed to inhalation anesthetics in a sample of 3 operating rooms]. / Valutazione di un protocollo di sorveglianza sanitaria per il personale esposto ad anestetici inalatori in tre sale operatorie campione.

OBJECTIVES: To verify the results of a health surveillance protocol for personnel exposed to inhalation anaesthetics. DESIGN: Yearly follow-up of operating room personnel. SETTING: Operating theatres of a university hospital; one "clean" room with waste anaesthetic scavengers, a second older room an thus "dirty", a third room with appropriate technical requirements, but with a considerable environmental emission of anaesthetics. PATIENTS OR PARTICIPANTS: Twenty-four technical surgical assistants and anaesthesiologists. INTERVENTION OR METHODS: Determination of the number of changes of air by means of concentration decay; determination of the baseline and final value of the environmental anaesthetics by infrared photoacoustic spectroscopy; analysis of the microclimate and inspection of the equipment. Determination of anaesthetics in the urine of personnel at the end of the work shift, using a gas-chromatograph with head space. Yearly medical check-up and blood tests. RESULTS: In the first year of observation we found values of nitrous oxide in one room and of isoflurane in all three rooms which exceeded the upper limit value. Acceptable values in all the rooms were detected during the second year. The values of anaesthetics found in urine samples reflected those measured in the rooms. Personnel reported subjective symptoms, but no blood alterations related to exposure were found. CONCLUSIONS: The application of the protocol has allow us to estimate the level of pollution and to suggest behavioral rules and technical precautions that have decreased the emission of anaesthetics in the environment. Blood tests are not a valid index of possible damage caused by exposure.

[Qualitative characteristics of human exposure to air chemical pollutants in operating rooms]. / Caratteristiche qualitative dell'esposizione umana a contaminanti chimici aerodispersi in sale operatorie.

UNLABELLED: For more than two decades many studies have been published searching for a link between exposure to volatile anaesthetic agents and health damage even if it is noteworthy that many other chemical substances can be found in the Operating Room. Purpose of this study was to demonstrate that the Operating Room is not a totally confined environment and that it is possible to perform an, at least qualitative, evaluation of many different polluting contaminants, even unexpected, to whom the working staff is exposed. MATERIAL AND METHODS: The study has been performed in the Operating Rooms of the Departments of Urology and Orthopaedics. Two methods have been employed: a long-casting sampling of volumes of air (with a sampling device composed of an enrichment system and a low flow aspirating pump) and an anaesthetic vapours and gas continuous analyzer. Results. We never recorded environmental levels of anesthetic higher than the currently accepted ones. Many other organic compounds of different kind have been found (irritants, cancer-organs). Their presence, not desirable in a place where a demanding work is performed, deserve further investigation and a quantitative evaluation of these compounds.